Gippsland Water Factory, Victoria, Australia

The Gippsland Water Factory, an innovative wastewater treatment and recycling facility, is the first of its kind in Australia. The plant opened in November 2009.

With a capacity to treat 35 million litres daily, the plant is providing the local industry with up to eight million litres of Class A recycled water. Ultimately, the intention is to recycle all of the water entering the plant.

The project was delivered by the Gippsland Water Factory Alliance. The alliance was formed expressly to design, build and commission the plant, and comprises Gippsland Water as principal sponsor with a consortium of three specialised companies: CH2M HILL, Parsons Brinckerhoff and Transfield Services.

In addition to the water factory, the work involved the construction of some 75km of allied pipelines and eight sewer pumping stations. The project entailed an overall investment of A$300m.

Gippsland water factory background

The facility was principally built to address a 50-year-old odour problem with the Regional Outfall Sewer, largely arising from an open-channel section that accounts for almost half of its 87km total length.

In addition to dealing with environmental concerns, the recycled water is proving to be beneficial to the industry, with Australian Paper signing up as its first customer.

The attraction of a secure source of high-quality recycled water will provide a boost to the local economy by encouraging commercial growth and generating new employment.

Drawing heavily on green engineering to guide the plant's design and approach to construction, the alliance saw the water factory as a key step in making the region a national leader of water sustainability and innovation.

To this end, the possibility of generating electricity on site to meet the plant's operational needs was also considered, while educational programmes and a visitor centre are planned to promote messages of sustainability.

The water factory will also help to protect and restore the region's lakes and waterways.

Wastewater treatment and recycling plant design

Planning and design work for the wastewater treatment and recycling plant began in January 2006, with construction starting 13 months later.

Although scheduled for completion by the end of 2008, the work was delayed for a year and opened in November 2009. Gippsland Water will take over full responsibility for the operation and maintenance of the facility after the two-year commissioning period.

The treatment / reclamation process uses biological treatment, micro-filtration and finally, reverse osmosis. A total of 12 cells, each containing 216 membrane modules, form the core of the membrane filtration system, with eight dedicated to treating domestic wastewater and the remainder for industrial flows.

The membrane bioreactor (MBR) approach taken at the plant combines tried-and-tested Memcor membrane filtration with activated sludge treatment to enable the required standards for water re-use.

Overall process efficiency is improved significantly by the membranes' high-retention of biosolids, enabling them to be returned for improved biological treatment. The plant's performance is further enhanced by the use of low-pressure membranes within the biological reactor system.

This removes the requirement for sedimentation and media filtration to remove suspended solids or mixed liquor from the treated flow. As well as simplifying the whole procedure, this also reduces the overall footprint.

A further key feature of the Memcor design is the unique two-phase jet fluid renewal system, which has been designed to ensure that water, solids and air are evenly distributed within each membrane module. At the same time, the cross-flow dynamics and cleaning arrangements minimise its energy demand.

The facility's MBR is housed within a doughnut-shaped structure.

The remaining treated water follows the existing discharge arrangements, flowing along the Regional Outfall Sewer to reach the deep ocean outfall, 1.2km from the shoreline.

Key players

Gippsland Water, the second-largest regional water authority in Victoria, was the water factory's principal sponsor, with project management provided by Transfield Services and engineering services by CH2M HILL and Parsons Brinckerhoff.

The plant's MBR system was supplied by Siemens Memcor. Other local contractors involved include Boom Logistics, GBG Concreting, Morrow Plumbing, Nilsen and SM Urban.